Table of Contents
Advertisement
The high static option supply fan motor is equipped with a pi-
lot-circuit Thermix combination over-temperature/over-current
protection device. This device resets automatically. Do not by-
pass this switch to correct trouble. Determine the cause and
correct it.
CONDENSER FAN MOTOR PROTECTION
The condenser fan motor is internally protected against over-
temperature.
Relief Device
A soft solder joint at the suction service access port provides
pressure relief under abnormal temperature and pressure condi-
tions (i.e., fire in building). Protect this joint during brazing op-
erations near this joint.
Control Circuit, 24-V
The control circuit is protected against overcurrent conditions
by a circuit breaker mounted on control transformer TRAN.
Reset is manual.
3-Volt
Lithium
Battery
LonWorks
Option Card
Port
J15
Example set for
BACnet MS/TP
and 76.8K baud
(1, 2, and 4 ON)
Recommended for all
i-Vu Open installations
J4
BO-1
J12
Protocol Selector
*Remove
both for 0-5V
Fig. 48 — RTU Open Control Module
RTU OPEN CONTROL SYSTEM
The RTU Open controller is an integrated component of the
Bryant rooftop unit. Its internal application programming pro-
vides optimum performance and energy efficiency. RTU Open
enables the unit to run in 100% stand-alone control mode or a
Third Party Building Automation System (BAS). On-board
DIP switches allow the user to select your protocol (and baud
rate) of choice among the four most popular protocols in use
today: BACnet, Modbus
Fig. 48.
The RTU Open control is factory-mounted in the unit's main
control box, to the left of the UCB (unit control board). Factory
wiring is completed through harnesses connected to the UCB.
Field connections for RTU Open sensors will be made at the
PCB connectors on the RTU Open board. The factory-installed
RTU Open control includes the supply-air temperature (SAT)
sensor. The outdoor air temperature (OAT) sensor is included
in the FIOP/accessory EconoMi$er
1. LonWorks is a registered trademark of Echelon Corporation.
2. Modbus is a registered trademark of Schneider Electric.
Board Power
J1
BO-2
BO-3
BO-4
J22
AO-2
GND
(2-10V)
J13
J17
J19
J20
SPT (temp input)
SPT (common)
SPT (offset input)
26
, Johnson N2 and LonWorks
1
®
2 package.
(AO-1)
0-10VDC
J3
J2
4-20mA
J5
BO-5
J22
VAF Output
BO-6
J11
BO-6
BO-7
(H) Humidimizer
BO-8
BO-8
(Power Exhaust)
Network Comm
J14
BACnet, Modbus, or N2
(LON connection J15)
. See
2
J5
Advertisement
Table of Contents
Troubleshooting
